“The growth charts are just one tool pediatricians use to help gauge whether a child is growing properly and as expected,” says Wolfson. Falling into a high percentile doesn’t mean that your child is healthier, nor does it mean your child has a growth problem if he falls into a lower one. What is important is that your child—whether he falls on the 5th or the 95th percentile curve after infancy—continues to follow that curve as he gets older. “It’s when a child deviates from the curve that we investigate further,” says Wolfson. “We want to find out if there’s a problem.”

This is why it’s vital that you bring your child to the pediatrician for an annual checkup. By comparing your child’s current spot on the growth chart with measurements from previous visits, your pediatrician will be able to ascertain whether your child is growing normally. Here are some growth chart deviations that indicate something may be amiss:

• When weight or height percentile changes from a pattern it’s been following. Let’s say your child’s height and weight have followed the 65th percentile line pretty consistently for fi ve years. At age 6, both height and weight suddenly drop into the 35th percentile. An unexpected slowing in a child’s growth pattern could indicate a health problem. “Ideally, a child should be growing along a curve,” says Parker. “Many things infl uence growth—nutrition, exercise, psycho-social factors, hormones, genetics—and we’d want to find out what caused the change.”

• Gaining weight at a faster clip than she’s gaining height. Your doctor may want to discuss your child’s diet and exercise habits if she’s in the 30th percentile for height, but the 80th for weight. (That is, she’s taller than only 30 percent of her peers, but weighs more than 80 percent of them.) “By age 4 to 5, a child knows where the snack cabinet is,” says Wolfson. “This is the age when weight may curve up more than it should.” (In addition to height and weight growth charts, pediatricians also use BMI growth charts beginning at the age of 2.) On the other hand, if your daughter has followed this curve consistently over the years, your doctor may conclude that she’s heavier than most kids her age due to genetics and that she’s growing normally.

• A gain in height but not in weight. This means your child is getting taller but isn’t gaining weight proportionately. “If weight is falling off, the fi rst thing we want to fi nd out is whether the child is getting enough calories,” says Wolfson. If it’s determined that he is getting proper nutrition, doctors would want to examine whether a child is absorbing the calories or has an intestinal abnormality. Again, this may also be the child’s normal growth pattern depending on genetics.